Draft-regulator.



, H. T. CORNWALL.

DRAFT REGULATOR.

APPLICATION FILED MAR. a, 1909.

2 SHEETS-SHEET 1.

Invento T.

Patented Jan. 11,1910.

H. T. CORNWALL.

DRAFT REGULATOR.

APPLICATION FILED MAR-3. 1909.

2 SHEETS-SHEET 2.

Patented Jan. 11,1910.

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DRAFT-REGULATOR.

T all whom "it may concern:

Be it known that I, HANFORD T. CORN- WALL, a citizen of the UnitedStates, residing at Brockton, in the county of Essex and State ofMassachusetts, have invented new and useful Improvements inDraft-Regulators, of which the following is a specification.

This invention relates to an improved device for regulating the draft insmoke fines and pipes for furnaces boilers and the like.

The object of the invention is to provide a draft regulator which can beoperated either automatically by means of a suitable diaphragm regulatoror by hand as may be desired.

The invention consists in the combination and arrangement of parts setforth in the following specification and particularly pointed out in theclaims thereof.

Referring to the drawings: Figure 1 is a side elevation of my improveddraft regulator showing the same attached to a smoke pipe, the smokepipe being broken away to save space in the drawings, the parts outsidethe smoke pipe being in the position which they occupy when the damperis closed. Fig. 2 is an end elevation as viewed from the right of Fig.1, with the smoke pipe shown in section. Fig. 3 is a side elevationsimilar to Fig. 1, with the parts in the positions occupied when thedamper is open. Fig. 1 is a sectional elevation taken on line 44 of Fig.2. Fig. 5 is a sectional elevation taken on line 55 of Fig. 1. Fig. 6 isa detail section taken on line 66 of Fig. 1. Fig. 7 is a diagrammaticview illustrating my improved draft regulator applied to the smoke pipeofa boiler. Fig. 8 is a side elevation similar to Fig. 1 showing amodified form of my invention. Fig. 9 is a detail sectional elevationtaken on line 9-9 of Fig. 8.

Like numerals refer to like parts throughout the several views of thedrawings.

In the drawings, 10 is a boiler, 11 the smoke pipe leading from saidboiler, 12 my improved draft regulator, 13 an endless chain extendingover pulleys 14:, 14. and connected to my improved draft regulator, ashereinafter fully described, and also connected tothe arm 15 of thediaphragm regulator 16, the construction of which is well known to thoseskilled in this art.

The draft regulator 12 consists of a primary damper 17 which isjournaled to r0- Specification of Letters Patent.

Application filed March 3, 1909.

Patented Jan. 11, 1910.

Serial No. 481,200.

tate within the smoke pipe 11 and upon rods 18 and 19 fastened toopposite sides, respectively, of the auxiliary damper 20, said auxiliarydamper being of a hollow hemispherical shape with the concave portionthereof opening toward that end of the smoke pipe which is attached totheboiler or furnace. At the left hand side of the primary damper 17 aboss or sleeve 21, preferably integral with said damper, extends throughand is journaled to rotate in a collar 22 which is fastened to the smokepipe 11. (Fig. 5). The rod 19 which is fastened to the auxiliary damperis journaled in the smoke pipe 11 and is prevented from movinglongitudinally thereof by nuts 23 on the outside of the smoke pipe. Therod 18 projects through the primary damper 17 and through the collar 22.

A bell-crank lever 24 having a horizontal arm 25 and a vertical arm 26is fastened by a screw 27 to the sleeve hub 21 of the primary damper 17.The outer end of the arm 25 has fastened thereto the chain 13 whichleads to the lever 15 of the diaphragm regu lator 16.

The rod 18 has an arm or lever 28 fast thereto, the lower end of whichrests against a stop-pin 29 when the parts are in the positionillustrated in Fig. 1. The upper end of the arm 28 has another arm 30fast thereto and to this arm 30 a weight 31 is adjustably fastened bymeans of a set-screw 32. A cross-bar 33 is adjustably fastened to theupper portion of the arm 28 by means of a set-screw 34 and thiscross-bar has cars 35, 35 projecting horizontally therefrom toward thesmoke pipe 11. The vertical arm 26 of the bell-crank lever 24 projectsupwardly between these ears 35, It will be noted that the primary damperand the auxiliary damper may be rotated independently of each otherabout a common axis extending transversely of the smoke pipe 11.

The general operation of the device hereinbefore specifically describedand illustrated in Figs. 1 to 7 inclusive is as follows: As suming theparts to be in the position illustrated in Figs. 1 and 4t and thepressure of steam decreases. then the diaphragm regulator lever 15 willmove upwardly at the right hand end thereof (Fig. 7), thus moving thechain 13 upwardly and moving the horizontal arm 25 of the bell-cranklever 24 upwardly. This will cause the primary damper 17 to rock aboutits axis and par tially open the space between the interior of the smokepipe and the periphery of the auxiliary damper, and this operation willcontinue until the vertical arm 26 engages the ear 35 at the left handend of the cross bar 33 (Fig. 1), whereupon the arm 28 will be tippedtoward the left at its upper end and both of the dampers will then beginto open. When the arm 28 has tipped the auxiliary damper to such anangle at the left of its position in Fig. 1 that the center of gravityshall have passed beyond a vertical plane extending through the commonaxis of the dampers 17 and 20, then the weighted arm 28 will cause saidarm and auxiliary damper to tip to its extreme open position asillustrated in Fig. 3 and as illustrated in dotted lines (Fig. i and theupper portion of the arm 28 will come to a rest against the pin 29 Thesmoke pipe will then have the draft turned on to its full extent and asthe steam pressure increases, the lever 15 will be moved upwardly at theleft of its pivot and downwardly at its right hand end, thus loweringthe chain 13 (see Fig. 7) adjacent to said lever 15 and moving the arm25 of the bell-crank lever dow wardly, thus rocking the arm 26 of saidlever toward the right from the position illustrated in Fig. 3 to thatillustrated in Fig. 1 and moving the different parts from the positionillustrated in Fig. 3 to that illustrated in Fig. 1 and from theposition illustrated in dotted lines (Fig. l) to that illustrated infull lines in said figure. It will be noted that by adjusting the weight31 toward the right (Fig. 1) the center of gravity of the auxiliarydamper and the arms attached thereto will be moved farther toward theright of the vertical plane extending through the common axis of theauxiliary and primary dampers, and by moving said weight toward the leftthe center of gravity of such combination of levers andthe auxiliarydamper will be moved toward the left, so that during the operationhereinbefore described the movement of the auxiliary damper into its extreme position, as shown in dotted lines (Fig. 4) will commence sooneror later according to the position of the weight 31 upon the arm 30.This time may also be regulated by moving the cross-bar 33 upwardly ordownwardly upon the upper end of the arm 28, so that the end of the arm26 will engage the ears 35 sooner or later comparatively.

The movement of the outer or primary damper 17 is suflicient for allordinary changes which are required in the draft in the smoke pipe, sothat the gases which are located near the pipe are the ones which willordinarily be affected by the operation of my improved draft regulatorwithin certain limits, but when it is desired to throw the damper wideopen, then both auxiliary and primary dampers are thrown into thepositions shown in Fig. 4t in dotted lines, as when, for instance, a newtire is being built or when coal is fed to the fire.

It will be noted that the edge 20 of the auxiliary damper (see Fig. ismade comparatively thin so as to obstruct as little as possible thepassage of the smoke and gases as they pass from the boiler to thechimney flue when the primary damper 17 is open or ctnnparatively open.It will also be understood that in the general operation of my improveddraft regulator, the object is to manipulate the primary damper to acertain extent without having any effect upon the position of theauxiliary damper 20 and the primary damper being located adjacent to theinner surface of the smoke pipe will regulate the gases and smoke whichare located near the inner surface of said smoke pipe, bat the highlyheated gases and products of combustion are always to be foundsubstantially in the center of the smoke pipe or flue and the auxiliarydamper is so located and so formed as to hold back these heated gasesand products of combustion and thus increase the efficiency of theboiler by saving the heat units contained within said heated gases andproducts of combus tion and holding them back in the boiler.

In the form of my invention illustrated in Figs. 8 and 9 the regulatoris adapted to be operated by hand. The form of my invention illustratedin'Figs. 1 to 7 can also be operated by hand if the chain 13 isdisconnected. Referring, then, to Figs. 8 and 9, 11 is the smoke pipe,12 is the draft regulator and the primary and auxiliary dampers are thesame as in the form of my invention 'hereinbefore described. The lever25 is provided with a handle 36 by which itis operated and said lever 25is fast to the primary damper. Said lever 25 is provided with a springlatch 37 which is pivoted at 38 to said lever, the inner end of thelatch being adapted to engage teeth 39 formed upon a flange 40 upon thecollar 22. The lever 28 is fastened to the auxiliary dampet and isprovided with a spring latch 37 which is also adapted to engage theteeth 39 and lock said lever 28 and the auxiliary damper in position. Inoperating this form of my device, the two auxiliary levers 25 and 28 areoperated by hand and are unlocked from the collar 22 by rocking thespring latches 37 and 37, respectively, until they are out of engagementwith the teeth 3t and then moving the lever 25 or the lever 28 to thedesired position, when upon releasing the spring latch 37 or 37, thesame will spring into engagement with the teeth 39 and lock the lever 25or 28 in position.

Having thus described my invention, what I claim and desire by LettersPatent to secure is:

1. In combination, a smoke pipe, a primary damper consisting of a ringand an auxiliary damper located within said ring, both of said dampersjournaled to rotate independently of each other within said smoke pipeabout a common axis extending transversely of said smoke pipe, meansoutside said smoke pipe whereby said primary damper may be rotated, andother means adapted to be operated by said first named means, wherebysaid auxiliary damper may be rotated.

2. In combination, a smoke pipe, a pri mary damper consisting of a ringand an auxiliary damper located within said ring, both of said dampersjournaled to rotate independently of each other within said smoke pipeabout a common axis extending transversely of said smoke pipe, an armoutside said smoke pipe fast to said primary damper, another arm outsidesaid smoke pipe fast to said auxiliary damper, said pri mary damper armadapted to engage and rotate said auxiliary damper arm.

3. In combination, a smoke pipe, a primary damper consisting of a ringand an auxiliary damper located within said ring, both of said dampersjournaled to rotate independently of each other within said smoke pipeabout a common axis extending transversely of said smoke pipe, an armoutside said smoke pipe fast to said primary damper, another arm outsidesaid smoke pipe fast to said auxiliary damper, and weighted tooverbalance said auxiliary damper, and means adapted to limit themovement of said weighted arm in opposite directions, said primarydamper arm adapted to engage and rotate said auxiliary damper arm.

4c. In combination, a smoke pipe, a primary damper consisting of a ringand an auxiliary damper located within said ring, both of said dampersournaled to rotate independently of each other within said smoke pipeabout a common axis extending transversely of said smoke pipe, a bellcrank lever outside said smoke pipe fast to said primary damper, anotherlever outside said smoke pipe fast to said auxiliary damper, a cross-barfast to said auxiliary damper lever with lugs projecting horizontallytherefrom at its opposite ends, one arm of said bellcrank leverprojecting between said lugs.

5. In combination, a smoke pipe, a primary damper consisting of a ringand an auxiliary damper located within said ring, both of said dampersjournaled to rotate in dependently of each other within said smoke pipeabout a common axis extending transversely of said smoke pipe, abell-crank lever outside said smoke pipe fast to said primary damper,another lever outside said smoke pipe fast to said auxiliary damper andweighted to overbalance said auxiliary damper, means adapted to limitthe movement of said weighted arm in opposite directions, a cross-barfast to said auxiliary damper lever with lugs projecting horizontallytherefrom at its opposite ends, one arm of said bell-crank leverprojecting between said lugs and adapted to play therebetween.

6. In combination, a smoke pipe, a primary damper consisting of a ringand an auxiliary damper located within said ring, both of said dampersjournaled to rotate independently of each other within said smoke pipeabout a common axis extending transversely of said smoke pipe, an armoutside said smoke pipe fast to said primary damper, another arm outsidesaid smoke pipe fast to said auxiliary damper, a weight fast to saidauxiliary damper arm adjustable relatively to a vertical planecontaining said axis and adapted to overbalance said auxiliary damper,and means adapted to limit the movement of said auxiliary damper arm inopposite directions, said primary damper arm adapted to engage androtate said auxiliary damper arm.

7. In combination, a smoke pipe, a primary damper consisting of a ring,and an auxiliary damper located within said ring, both of said dampersjournaled to rotate independently of each other within said smoke pipeabout a common axis extending transversely of said smoke pipe, meansoutside said smoke pipe, whereby said primary damper may be rotated, andother means adapted to be operated by said first named means, wherebysaid auxiliary damper may be rotated, a boiler, a regulator connected tosaid boiler, and means operatively connecting said regulator to saidfirst named means.

8. A draft regulator adapted to be inserted in a smoke pipe having, incombination, a primary damper consisting of a ring, and an auxiliarydamper consisting of a hollow hemispherical member located within saidring, the greatest diameter of said hemispherical member beingapproximately equal to the spherical diameter of said member, saidprimary damper and auxiliary damper being journaled to rotateindependently about a common axis.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

HANFORD T. CORNIVALL. l/Vitn esses CHARLES S. Goonme, LOUIS A. J ones.

